Mobility ping over EoIP—This test runs over EoIP - IP port 97 and tests the mobility data traffic over the management interface.
Note: Only one mobility ping test per controller can be run at a given time.
If there is a firewall present, make sure that the UDP port 16666 and IP port 97 are opened for communication between the WLCs.
My Question is, IP port 97 means TCP port 97 or UDP port 97, or both? I captured the communication between the Anchor controller and non-anchor controller, I couldn't see any packet with TCP or UDP port 97. Perhaps it's encrypted by LWAPP.
I did a quick FW / WLC topology that may be helpful to you ...
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